The tank I have questions about is a 75g bare bottom, mixed reef tank that I have had set up for almost 10 years now. I have been wanting to add sand to it for a couple of years now so I can have access to more fish and inverts, plus I love the look of it. My concern is that it will shock my coral and existing fish? I have had and still have plenty of sand bottoms, but never converted a bare to sand. I know it is really bad to go established sand to bare bottom, anyone have any advice or experience, maybe adding small amounts of sand over a long period?